(1) Field of the Invention
This invention relates to the two-dimensional selection of portions of a computer display area and the two-dimensional selection of the portions of information to display within the selected display area. Specifically, the field is that of interactive computer display control devices where a selected portion of the available information is viewable in a selected portion of the display area.
(2) Prior Art
Information management systems are placing increasing demands on the physical resources available for displaying information to the user. Currently, the art in computer display management provides the capability of displaying data in rectangular portions (commonly referred to as windows) of a display screen. The closest art know to the applicant is the Finder.TM. interface of the Apple Macintosh.TM. computer, manufactured by Apple Computer, Inc. of Cupertino, Calif. Controls are typically provided to resize and move windows within the confines of the physical display boundaries. Additional controls are also provided to shift the viewable portion of information within the limits of the previously defined window boundaries. This shifting of the viewable portion of the information is known as scrolling. One control means is typically provided to scroll the information horizontally; another control means is provided to scroll the data vertically. The prior art does not provide a means for scrolling the viewable portion of the information simultaneously in two dimensions without manipulating the display area directly. Current scrolling methods require the user to position the cursor inside of the window containing the information and to set the viewable region by movement of the cursor. This method may create problems if the information window is not completely viewable or the information for display is voluminous. Prior art also does not provide the capability for dynamic feedback as the viewable portion of the data is being selected. Current windowing capabilities do not provide the means for displaying, in a separate area of the display screen, a graphic two-dimensional representation of the position and size of the portion of the available information that is presently viewable. Prior art typically does not allow windows to be sized or moved beyond the physical boundaries of the display area. Windows usually need to be within view and not hidden in order to be manipulated by the devices available in the prior art. These capabilities are significant for the efficient use of a limited display area. The present invention provides these display management advances.